Curtain coating machine



May 12, 1964 L- A. WANDTKE 3,132,968

CURTAIN COATING MACHINE Fild Ndvl 15, 1961 FIG. I

IN VEN TOR. LARRY A. WANDTKE United States Patent This invention relates to that type of machine which applies paint or other liquid material onto articles by means of a curtain of the material through which the articles to be coated or processed are passed.

It will be apparent that with the use of the above mentioncd type of machine, it occasionally becomes necessary to clean the machine and to perform maintenance work thereon. Also, at times it may be necessary to change the type of coating when coating different types of articles or applying different coatings on the same article. Such cleaning, maintenance and/or changing of the coating material is a very bothersome and time consuming procedure. Heretofore, for these jobs it necessitated shutting the machine down with consequent costly interruption of production.

Thus, one of the principal objects of the present invention is to provide a curtain coating machine wherein means is provided for reducing or substantially elim inating the interruption of production caused by cleaning, maintenance or changing of the coating material. A further object is to provide a pressure curtain coating machine wherein at least one of the heads thereof is adapted to be disposed in a position for production while at least another head thereof is in an off-line position for cleaning, maintenance, putting in new coating material, and/ or changing the coating material therein.

A further object is to provide, in such a machine, means so that the head in the off-line position may be tested and adjusted in preparation for use whereby no time is lost" on such testing and adjusting when the head is put into a position for production. i

A further object is to provide means for supporting the heads so that the heads are easily and quickly movable into the position for production or the off-line position, and are securely held in such positions.

A further object is to provide means for draining the coating material when in the off-line position.

A further object is generally to improve the design and construction of curtain coating machines.

- The means by which the foregoing and otherobjects of the present invention are accomplished and the man ner of their accomplishment will be readily understood from the following specification upon reference to the accompanying drawings, in which:

FIG. 1 is a side elevational view of the machine of the present invention. 7 i

FIG. 2 is a top plan View thereof. a

FIG. 3 is a diagrammatic view showing the operation of a pressure curtain coating machine. i

FIG. 4 is an enlarged fragmentary view of the supporting means for one of thecoating heads.

Referring now to the drawings in which the various parts are indicated by numerals, the curtain coating machine 11 of the present invention comprises a base 13 of usual construction which contains the usual mechanisms, such as drive motors, etc., not shown, that form no part of the present invention but are well known to those head 23 mounted across conveyor belt 17 in a fixed position for production. The head 23 which is shown disposed across the middle of base 13 in FIGS. .1 and 2 is in such a position .for production. However, in the curtain coating machine 11 of the present invention there are two pivotable heads 23 with only one at a time being in a position for production, as will be understood better in the description to follow later in the specification. Both of heads 23 are of usual construction and are well known to those skilled in the art. Thus, the following general description should sutfice.

Each of heads 23 comprises two principal parts, an outer portion 24 and an inner portion 25 slidably mounted in outer portion 24 for vertical upward or. downward movement in response to turn of a hand crank 26.

The actual coating operation performed by machines of the curtain coating type forms no part of the present invention, but a schematic diagram thereof is shown in FIG. 3 so that this figure, when considered in conjunction with FIGS. 1 and 2 and with the following description,

. will make possible an understanding of the general enskilled in the art. Base 13 is mounted on a supporting surface 15 as a floor or the like. I

The usual conveyor belt 17 is mounted on base 13 for movement over the top 19 of the base in the direction of the arrow indicated at 21. In the usual construction of a curtain coating machine there is at least one coating post 73 adjacent the opposite'end of base 13 and on the.

vironment of the present invention. Although in the drawings a curtain coating machine of a particular type is shown, i.e., a pressure curtain coating machine, it will be understood that this is for illustration purposes only and the present invention may be applied to any type of machine which applies paint or other liquid material onto articles by means of a curtain of the material through which the articles to .be coated or processed are passed.

Below the head 23 that is in a position for production a material collection trough 27 is disposed in a transverse recess 28 in base 13. Coating material 29 is pumped into the inner portion 25 against an entrapped air cushion 31. The coating material 29 is forced outwardly andv downwardly through an elongated transverse orifice 33 defined by a pair of spaced knives 35, 37. Thiscauses a thincurtain 39 of flowing material to be extruded downwardly onto the article 41 to be coated which is carried' through the curtain by the conveyor belt 17.v The conveyor belt 17 is carried downwardly andaround trough 27 byisuitablerollers' 43 so that the coating material which flows beyond the opposite side edges of the articlev on supporting surface 15 adjacent base 13 and extends over thebase. Framework'53 includes a pair of vertical posts 55, 57 which are supported from supporting surface 15 respectively by rectangular structures 59, 61. Each of structures 59, 61 are substantially identical, and the following description of structure 59 will suifice' for. both.

Structure '59 comprises a pair of upstanding and hori- Zontally spaced legs 63, 65 which are rigidly interconnected by cross pieces 67, 69. Post 55 extends'through an aperture in cross piece 67 and is fixedly :aittaohedadjacent the'lower end thereof to cross piece 69. The purpose of rectangular structures 59, 61 is so that the tank 45, which is preferably provided with wheels 71, can be rolled into.

place beneath trough 27. It will be understood that the tank 45 is placed between legs 63, 65, which would otherwise not be possible if post 55 were extended downwardly.

to supporting surface 15. Framework 53 additionally includes another vertical post 73 adjacent one corner of base 13 in spaced relationship .to post 55 and on the same side of base 13 as post 55. In addition, framework 53 includes a vertictal post 75 diagonally disposed relative to same side of base 13 as post 57. Additionally, framework 53 includes overhead members 77, 7 9, 83, 85 and 87 fixedly attached adjacent the upper ends of the posts in the following arrangement. Member 77 extends between posts 55 and 73, member 7 9 extends between posts 57 and 75, member 83 extends between posts 55 and75, member 85 extends between posts 57 and 73, and member 87 extends between posts 55 and 57. Thus, members 77, 7 9, 83 and 85 form substantially a. parallelogram when viewed from above, as in FIG. 2, and member 37 extends transversely across and above base 13 between two opposite angles of the parallelogram. The members 83 and 85 extend in parallel relationship diagonally across base 13, and the members 77 and 79 extend in parallel relationship longitudinally of the base on opposite sides thereof.

One end of one of heads 23 is pivotally supponted from post 55 by means of an arm 89 which comprises a sleeve 91 rotatably disposed around the post and a horizontal pipe 93 fixedly attached adjacent One end to sleeve 91 and fixedly attached adjacent the opposite end to the head 23. A ring 95 is fixedly and adjustably attached on post 55 below sleeve 91 to support the sleeve. Thus, this head 23 is pivotally mounted for pivot about a vertical axis that coincides with the center line of post 55. At the opposite end of this head 23 from arm 89 is provided a suitable clamp 97 which is rernovably engaged on post 73. A trolley 9 9 is disposed between this head 23 and an arcuate track 101, which track is fixedly attached to members 7 7, 85 and 87 and describes the arc of a circle whose center coincides with the center line of post 55. Track 1M is preferably I-shaped in cross section. In other words, the track 101 includes a vertical web portion 103 and horizontal upper and lower portions 104, 105. Lower portion 135 is engaged by a pair of rollers 107, 109 which form part of the trolley 99 and which trolley additionally includes a U-sbaped bracket 111 upon which the rollers are rotatably mounted. Bracket 111 is attached to the head 23 by adjustable means as the turnbuckle 113 of usual construction so that the support given to the head may be adjusted by means of the turnbuckle.

A similar arrangement is provided for the other of heads 23,'which other head is supported from post 57 by 4 opposite ends of the trough which support the trough from inner portion 25. Also, it should be noted that the discharge outlet 123 of trough 27 has attached thereto a drain conduit 125 which conducts the material from trough 27 into tank 45. Conduit 125 is preferably flexible and in the ifOIlTl of a rubber hose so that the head may be pivoted with the lower end of conduit 125 remaining in tank 45. This arrangement is advantageous because of the time saved in not having to completely drain trough 27 before pivoting the head 23. The trough 27 of the head 23 which is in the position for production is normally in an unattached position beneath the head, as shown in FIG. 3, so that to ready this head for pivoting to its offline position, shown in dotted lines in FIG. 2, it is necessary to first attach the trough to the inner portion 25, as by the hangers 121 heretofore described, and then raise the inner portion by turning hand crank 127 to carry the trough into the raised position above top 19. Then, this head 23 is swung into the off-line position, shown in dotted lines, and clamped in place. A similar annangement to that heretofore described, including a flexible conduit,

not shown, is provided for draining the coating material into a tank, not shown, disposed on that side of the base 13 and similar -to tank 45 heretofore described. Next, the head 23 which was in the off-line position may be pivoted about post 55 to the position for production previously occupied by the other head 23. Then the trough 27 of means of an arm 115 similar to arm 89. Likewise, a clamp 117 similar :to clamp 97 is provided for this other head,

and a track 119 similar to track 161 is supported from members 79, 83 and 87 to establish with a trolley, not shown, like trolley 99, the means by which this other head 23 is supported from the framework 53. Track 119 forms an arc of a circle with (the center thereof coinciding with the center line of post 57.

In the drawings the head 23 which is pivotable about post is shown in the off-line position and the other head 23 which is pivotable about post 57 is shown in the position for production to coat articles on the conveyor belt 17. It will be observed that the head 23 which is in the off-line position is disposed to one side of base 13 and generally parallel with the longitudinal axis of the base. Also, it will be noted that this head23 in the off-line position extends between posts 55 and 73 the clamp 97 being clamped about the post 73 to hold securely the head in this position. Also, it will be noted that the head 23 in the position for production extends transversely of base 13 between posts 55 and 57 with clamp 117 being attached to post 55. When the head 23 is in this position (for production, the head extends over the trough 27 as heretofore described relative to FIG. 3.

' When it is desired to change the paint, perform maintenance work, or to clean one of the heads 23 which is in a position for production, it will be understood that to save time the head 23 which is in the otfdine position is prepared for use. It should be noted that the head 23 in the offline position has the inner portion 25 in a raised position and the trough 27 is in an upper position above the level of top 19. Trough 27 is supported in this upper position by any suitable means as hangers 121 at the this head is detached from inner portion 25 and placed in position below the top 19, as shown in FIG. 3, and the inner portion 25 is lowered to the desired heigit.

From the foregoing it will be understood that a coating machine 11 is provided in which the interruption of production caused by the cleaning and maintenance of the machine or changing of the paint is reduced or substantially eliminated, particularly as compared with previous types of coating machines in which the head had to be maintained, cleaned and the paint changed while in position for production on the machine. Additionally, it will be understood that in the present invention the head 23 in the off-line position may be completely tested and adjusted since this head may be operated and the coating material drained into tank 45. This is ,asubstantial saving in time as compared with previous ma.- chines which had their production further interrupted after cleaning, etc. by having to test and adjust the machine before starting regular production. It will further be understood that such a coating machine is provided in which the heads are easily and quickly movable into the position for production and the off-line position and, once moved into these positions, are securely held in place. In addition, it will be understood that since the framework 53 is supported independently of base 13, none of the vibration from machine 13 will be transmitted to the curtain 39.

Although the invention has been described and illustrated with respect to a preferred embodiment thereof, it is to be understood that it is not to be so limited since changes and modifications may be made therein which are within the full intended scope of this invention as hereinafter claimed.

I claim: 1.- In an apparatus for applying liquid material onto articles by a curtain of the material, a supporting surface, a base mounted on said supporting surface, conveyor means movably mounted on said base for conveying articles to be coated, a framework mounted on said supporting surface adjacent said base and extending over said base, at least one arcuate track mounted on said framework, at least one head means for discharging a curtain of the liquid material comprising an outerframe portion and an inner reservoir portion slidably mounted therein, said framework including at least one post on one side of said base, pivot means interposed between said head means and said post for pivotally supporting said head means from said post, means attached to said head means remote from said pivot means and engaging said track for movable support thereof from said framework, said head means being pivotable between an'ofiline position on one side of said base and a position for production above said conveyor means and means to raise and lower said inner reservoir portion in the outer frame portion.

2. In an apparatus for applying liquid material onto articles by a curtain of the material, a supporting surface, a base mounted on said supporting surface, conveyor means movably mounted on said base for conveying articles to be coated, a tank mounted on said supporting surface, a framework mounted on said supporting surface adjacent said base and extending over said base, at least one arcuate track mounted on said framework, at least one head means for discharging a curtain of the liquid material comprising an outer frame portion and an inner reservoir portion slidably mounted for vertical movement therein, said framework including at least one post on one side of said base, pivot means interposed between said outer frame head means and said post for pivotally supporting said head means from said post, means attached to said outer frame head means remote from said pivot means and engaging said track for movable support thereof from said framework, said head means being selectively pivotable from off-line positions on opposite sides of said base to a position for production above said conveyor means, and drain means including a trough beneath said head means and a flexible conduit extending between said trough and said tank for draining said head means regardless of its position, means to detachably connect said trough to said slidable inner reservoir portion of said head means, and means to raise and lower said inner reservoir portions and trough in said outer frame portion.

3. In an apparatus for applying liquid material onto articles by a curtain of the material, a supporting surface, a base mounted on said supporting surface, conveyor means movably mounted on said base for conveying articles to be coated, a framework mounted on said supporting surface adjacent said base and extending over said base, a pair of arcuate tracks mounted on said framework, a pair of head means for respectively discharging a curtain of the liquid material comprising an outer inverted U-shaped frame portion and an inner reservoir portion mounted for vertical movement therein, said framework including a pair of posts on opposite sides of said base, a pair of pivot means respectively interposed between said pair of head means and said pair of posts for pivotally supporting said pair of head means respectively from said posts, a pair of means respectively attached to said head means remote from said pivot means and respectively engaging said tracks for movable support thereof from said framework, said pair of head means being selectively pivotable from off-line positions on opposite sides of said base to a position for production above said conveyor means, and means to raise and lower said inner reservoir portion in said outer inverted U-shaped frame portion.

4. In an apparatus for applying liquid material, onto articles by a curtain of the material, a supporting surface, a base mounted on said supporting surface, conveyor means movably mounted on said base for conveying articles to be coated, a tank movably mounted on said supporting surface beneath said base, a framework mounted on said supporting surface adjacent said base and extending over said base; said framework including a first pair of spaced posts disposed on one side of said base, a second pair of spaced posts disposed on the other side of said base, and a plurality of members rigidly interconnecting said posts adjacent the upper ends thereof; a first head means for discharging a curtain of the liquid material comprising an outer frame portion and an inner reservoir portion slidably mounted for vertical movement therein, means interposed between the outer frame of said first head means and one of said first pair of spaced posts for pivotally supporting said first head means from said one of said first pair of posts, said first head means being pivotable between an off-line position between said first pair of spaced posts and a production position between said one of said first pair of posts and one of said second pair of posts, means attached to the outer frame of said first head means for securing said first head means selectively in said off-line position and said position for production, a first arcuate track attached to said framework, a first trolley means attached to the outer frame of said first head means and engaging said, first track for movable support of said first head means from said framework, first drain means including a first trough beneath said first head means and a first flexible conduit extending between said first trough and said tank for draining said first head means regardless of its position; a second head means for discharging a curtain of the liquid material comprising an outer frame portion and an inner reservoir portion slidably mounted for vertical movement in said outer frame portion, means interposed between the outer frame of said second head means and one of said second pair of spaced posts for pivotally supporting said second head means from said one of said second pair of posts, said second head means being pivotable between an off-line position between said second pair of said spaced posts and a production position between said one of said second pair of posts and one of said first pair of posts, means attached to the outer frame portion of said second head means for securing said second head means selectively in said off-line position and said position for production, a second arcuate track attached to said framework, a second trolley means attached to the outer frame portion of said second head means and engaging said second track for movable support of said second head means from said framework, and second drain means including a second trough beneath said second head-means and a second flexible conduit extending between said second trough and said tank for draining said second head means regardless of its position, means to detachably connect said troughs to the slidable inner reservoir portion of said first and second head means and means to raise and lower said inner reservoir portions and said troughs in said outer frame head means.

5. In an apparatus for applying liquid material onto articles by a curtain of the material, a supporting surface, a base mounted on said supporting surface, conveyor means movably mounted on said base for conveying articles to be coated, at least one head means for discharging a curtain of the liquid material comprising an outer frame portion and an inner reservoir portion slidably mounted therein, support means attached to said outer frame head means for pivotally supporting said outer frame head means for pivot between an off-line position to one side of said conveyor means and a position for production above said conveyor means, means for supporting said head outer frame means at the end opposite said pivotal support means when the head means is in position for production, and a support means comprising a curved track for supporting said head means in production and off-line position and as it is swung from production position to off-line position and back again, and means to raise and lower the inner reservoir portion in the outer frame portion.

6. In an apparatus for applying liquid material onto articles by a curtain of the material, a supporting surface, a base mounted on said supporting surface, conveyor means movably mounted on said base for conveying articles to be coated, a frame work mounted on said supporting surface adjacent said base and extending over said base, at least one head means for discharging a curtain of the liquid material comprising an outer frame portion and an inner trough portion slidably mounted therein, support means interposed between said framework and said outer frame head means for pivotally supporting said outer frame head meansfrom said framework, said head means being selectively pivotable between an off-line position on one side of said base and a position for production above said conveyor means, means for supporting said head outer frame means at the end opposite said pivotal support means when the head means is in position for production, and a support means comprising a curved track for supporting said head means in production and off-line position and as it is swung from production position to off-line position and back again, and means to raise and lower the inner reservoir portion in the outer frame portion.

7. The apparatus of claim 5 in which the pouring head is enclosed whereby the liquid coating material is pumped into said inner reservoir portion against an entrapped air cushion.

8. The apparatus of claim 2 comprising means to pass said conveyor beneath said trough below the normal level References Cited in the file of this patent UNITED STATES PATENTS 1,162,717 White Nov. 30, 1915 2,898,881 Straley Aug. ll, 1959 2,935,424 Glaus May 3, 1960 FOREIGN PATENTS 1,080,443 Germany Apr. 21, 1960 347,742 Switzerland Aug. 31, 1960 

1. IN AN APPARATUS FOR APPLYING LIQUID MATERIAL ONTO ARTICLES BY A CURTAIN OF THE MATERIAL, A SUPPORTING SURFACE, A BASE MOUNTED ON SAID SUPPORTING SURFACE, CONVEYOR MEANS MOVABLY MOUNTED ON SAID BASE FOR CONVEYING ARTICLES TO BE COATED, A FRAMEWORK MOUNTED ON SAID SUPPORTING SURFACE ADJACENT SAID BASE AND EXTENDING OVER SAID BASE, AT LEAST ONE ARCUATE TRACK MOUNTED ON SAID FRAMEWORK, AT LEAST ONE HEAD MEANS FOR DISCHARGING A CURTAIN OF THE LIQUID MATERIAL COMPRISING AN OUTER FRAME PORTION AND AN INNER RESERVOIR PORTION SLIDABLY MOUNTED THEREIN, SAID FRAMEWORK INCLUDING AT LEAST ONE POST ON ONE SIDE OF SAID BASE, PIVOT MEANS INTERPOSED BETWEEN SAID HEAD MEANS AND SAID POST FOR PIVOTALLY SUPPORTING SAID HEAD MEANS FROM SAID POST, MEANS ATTACHED TO SAID HEAD MEANS REMOTE FROM SAID PIVOT MEANS AND ENGAGING SAID TRACT FOR MOVABLE SUPPORT THEREOF FROM SAID FRAMEWORK, SAID HEAD MEANS BEING PIVOTABLY BETWEEN AN OFFLINE POSITION ON ONE SIDE OF SAID BASE AND A POSITION FOR PRODUCTION ABOVE SAID CONVEYOR MEANS AND MEANS TO RAISE AND LOWER SAID INNER RESERVOIR PORTION IN THE OUTER FRAME PORTION. 